BATON ROUGE, La. -- The head of Louisiana's charity hospital system says both of New Orleans' public hospitals were destroyed by Hurricane Katrina and need to be replaced, but a key official says it's too early to assume the federal government will pay for a new institution.

A central question is how much damage was caused by the storm and how much came earlier. Charity Hospital _ known as "Big Charity" _ and University hospital had deteriorating buildings that officials wanted to replace even before Katrina flooded them for weeks with 6 to 8 feet of water.

"One thing we will not address, and we've tried to be clear about this, we don't address the deficiencies that existed before the disaster," said David Fukutomi, the Federal Emergency Management Agency's infrastructure coordinator for Louisiana.

FEMA decides how much the federal government will pay, whether it will pay for repairs to the aging hospital buildings or whether the facilities are damaged beyond repair and it will pay for a replacement.

In either case, the system operated by the Louisiana State University Health Care Services Division could pool the money and build one new hospital.

But FEMA's payment would be the largest source of money since the hospital system, which runs nine hospitals around the state, already had been cutting services and paring its budget for years, and now has no income from the two New Orleans facilities.

"It is crucial," Don Smithburg, chief executive officer of the LSU Health Care Services Division, said of the federal money.

Engineers who assessed the damage for LSU determined that Big Charity was 65 percent ruined and University was 68 percent ruined, well above the 50 percent point used by FEMA to determine if a building should be repaired or replaced, Smithburg said.

Estimates to replace the two facilities would be about $567 million without equipment or furniture, he said. The hospital system would like to build one new hospital, probably smaller than the combined capacity of the two existing hospitals with an emphasis on outpatient services and trauma and specialty care.

However, Fukutomi said a multistory facility that had several feet of water on one floor would more likely be eligible for repair rather than replacement.

"It's unlikely that from what we know that that would trigger federal funding for a replacement," he said, adding: "It's not impossible. We're going to give them everything we're legally able to, but it may not meet their expectations."

Smithburg said he's been told that the hospitals' damage assessments would be taken into account by FEMA officials and that there was room for discussion.

FEMA doesn't have a projection for when it will decide on the amount of damage at the 18-story, 1930s-era Big Charity building or at the eight-story, 1950s-era University Hospital. Fukutomi said teams have done some preliminary assessments and are still at work.

Whatever price tag FEMA puts on the damage, the federal government will pick up 90 percent of the cost and the hospital system will have to find the remaining 10 percent. Smithburg said hospital officials will look at state and federal help, borrowing and private fundraising.